Transmission mechanism

ABSTRACT

An automatic transmission structure of the planetary type including a planetary gear set providing a plurality of forwarddriving ratios and a reverse-driving ratio and having remote means for applying a friction brake to establish one of the ratios, the remote means including an annular member extending from a hydraulic servomotor on one side of the planetary gear set to a friction brake mechanism on the other side of the planetary gear set so as to apply said friction brake remotely and further includes a sheet metal part interconnecting two elements of the planetary gear set and the output shaft of the transmission.

United States Patent [72] Inventor Robert Wayman Bloomfield Hills, Mich.[211 Appl. No. 845,806 [22] Filed July 29, 1969 [45] Patented Aug.17,1971 [73] Assignee Borg-Warner Corporation Chicago, Ill.

[54] TRANSMISSION MECHANISM 17 Claims, 3 Drawing Figs.

[52] US. Cl 74/763, 192/85, l88/72.4, 74/801 [51] Int. Cl ..F16h 57/10,Fl6d 51/00, Fl6d 25/00 50] Field of Search 74/762, 763; 192/85; 188/724[56] References Cited I UNITED STATES PATENTS 2,870,655 l/l959 RockwellI 74/785 Primary Examiner-Arthur T. McKeon Attorneys-Donald W. Banner,William S. McCurry and John W. Butcher ABSTRACT: An automatictransmission structure of the planetary type including a planetary gearset providing a plurality of forward-driving ratios and areverse-driving ratio and having remote means for applying a frictionbrake to establish one of the ratios, the remote means including anannular member extending from a hydraulic servomotor on one side of theplanetary gear set to a friction brake mechanism on the other side ofthe planetary gear set so as to apply said friction brake remotely andfurther includes a sheet metal part interconnecting two elements of theplanetary gear set and the output shaft of the transmission.

t TRANSMISSION MECHANISM I SUMMARY OF INVENTION In automatictransmission structures, a common problem is the utilization of a commontransmission case for more than one type of transmission to be includedin the case. There has been provided a transmission for a particulartype case for example which transmission provides four forward speedsand reverse between input and output shafts. The present inventionsolves one of the problems involved in that the servomotor used to applyone of the friction elements in the four-speed device is in a positionat the rear of the case and the frictional element to be applied whenthe device is modified for a threespeed planetary gear set is on theopposite side of the planetary gear set. Therefore, a novel mechanism isemployed to remotely apply the particular friction brake devicedisclosed herein.

In the present invention this difficulty has been solved by use of anannular tubular-shaped sheet metal force transmitting member whichextends between a hydraulic servomotor on one side of the gear set and afriction engaging device on the opposite side of the gear set and thusprovides that the friction engaging mechanism may be engaged from aremote position in the transmission. In addition, the force-transmittingmeans is made of sheet metal which may be conveniently manufactured froma tube or by rolling sheet metal into the form of a tube and securingthe sheet metal part to a hydraulic piston in the servomotor.

Further, the present invention provides an interconnecting element forthe gear set made of sheet metal which has a central radial portionconnected to one element of the gear set, a forwardly extending axialportion connected to another element of the gear set and a rearwardlyextending axial portion connected to the output shaft of thetransmission. The interconnecting element may be conveniently, forexample, welded to the two elements of the planetary gear set and byslotted connection connected to the output shaft of the transmissionmechanism.

DESCRlPTION OF THE DRAWINGS FIG. 1 represents a schematic view of thetransmission mechanism with which the present invention is used;

FlG. 2 is a cross-sectional view in detail of part of the transmissionmechanism; and

FIG. 3 is an end view of the annular forcetransmitting member shown inFlG. 2.

Referring to FIG. 1, a transmission mechanism is schematicallyillustrated. This transmission includes a transmission casing ll, aninput shaft 12 and an output shaft 13. Rotatably fixed in the case 11 isa stationary sleeve 15 which has incorporated therein several of thefriction engaging mechanisms for the transmission mechanism. Alsoprovided in the transmission case lil is a pair of clutches 28 and 21,friction brake mechanisms 23, 24 and 25 and a planetary gear set 27. Anintermediate shaft interconnects clutch 20 with an annulus gear M in thegear set, an intermediate shaft 34 interconnects clutch 21 with a doublesun gear arrangement 36 for the gear set 27. The planetary gear set 27further includes a planetary gear carrier 38 having planetary pinions 39journaled thereon and a planetary carrier 40 having planetary pinions 42journaled thereon. The planetary pinions 42 mesh with the annuhis gear32 and the sun gear 36. There is further provided an annulus gear 44meshing with planetary pinions 39.

A hydraulic servomotor is provided for clutch 20 and a hydraulicservomotor 52 is provided for clutch 21. A hydraulic servomotor 54 isprovided for friction brake 23 and a hydraulic servomotor 55 is providedfor friction brake 24. A hydraulic servomotor 58 is provided at the rearof the transmission case 11 for the friction engaging mechanism 25. Aone-way brake 60 is provided for the planetary carrier 38, a one-waybrake 62 is provided between friction brake 24 and intermediate shaft34.

Operation of the transmission mechanism as described above and relatingto the schematic showing in FIG. 1 is as follows: with clutches 20 and21 disengaged a neutral condition is established.

Low or first drive ratio is established by application of clutch 20connecting shaft 30 with input shaft 12 thereby driving annulus gear 31in the forward direction. The planetary carrier 40 is connected tooutput shaft 13 thereby providing a forward drive of the output shaft 13at a reduced speed, one way brake 60 holding planetary carrier 38 toprovide a reaction element for the planetary gear set. A manual firstspeed drive ratio similar to the one-way drive just described may beprovided by engagement of friction brake 25 by means of hydraulicservomotor 58 holding planetary carrier 38 against rotation in eitherdirection thereby establishing a two-way drive through the planetarygear set.

Second drive ratio is provided by clutch 20 remaining engaged andengagement of friction brake 24 by hydraulic servomotor 55 thus holdingthe sun gears 36 stationary. Under these conditions a higher speedforward drive is provided by the planetary carrier 40 being driven byinput shaft 12 at a reduced speed with one-way brake 62 being madeeffective to hold sun gears 36 stationary establishing a one-way driveconnection for second speed. Optionally brake 23 may be applied to holdshaft 34 against rotation in either direction to provide a two-waysecond speed drive ratio.

Third speed drive ratio is provided by clutch 20 remaining engaged andclutch 21 being engaged by hydraulic servomotor 52 thereby lockingshafts 34 and 30 together locking up the planetary gear set andproviding a l: 1 forward drive of the output shaft 13.

Reverse drive ratio is established by engagement of clutch 21 andengagement of friction brake 25 the sun gear 36 thus being driven en aforward direction planetary carrier 38 being held stationary and thusdriving annulus gear 44 and thereby output shaft 13 in the reversedirection.

Referring specifically to FIG. 2, a novel and improved structure foraccomplishing the operation of the above-described transmissionmechanism is illustrated in detail. Friction brake 25 has includedtherewith an apply plate or member 70 which is splined to sleeve 15 andis axially slidable to engage the friction engaging plates 72 of thefriction. brake 25. Provided in the hydraulic servomotor 58 is anaxially slidable member or piston 74 which is movable in response tofluid pressure against the force of a return spring 76 to move applyplate 70 to engage friction brake 25. An annular thrust-transmittingmember 78 is provided to provide a connection between piston 74 andapply plate 70. As discussed, the hydraulic servomotor 58 and piston 74is disposed on one side of gear set 27 and the friction brake mechanism25 is disposed on the opposite side of the planetary gear set 27. Thusthe friction brake 25 is remotely applied by means of annular member 78extending over the planetary gear set 27 between piston 74 and applyplate 70.

The member 78 is conveniently formed in an annular tubelike shape ofsheet metal which may be manufactured from a tube or by rolling a pieceof sheet metal to the desired shape. A projection 82 is provided in themember 78 which is received in a mating recess 84 in plate 70. Themember 78 is mounted within a bore in piston 74 and may be securedthereto by any known means, as for example, by rivets 92.

Referring to FIG. 3, an interruption in the circumference of member 78is provided resulting in terminal end portions 94 and 96 of the annularmember 78. This interruption is provided to allow access of the parkingbrake mechanism (not illustrated) to the planetary gear set.

A further improvement is provided in the present invention byutilization of a sheet metal torque=-transmitting member 102 in thetransmission combination which interconnects planetary carrier 40,annulus gear 44, and output shaft 13. The torque-transmitting member 102has a central radially extending portion 104, a forwardly extendingaxial portion 106 and a rearwardly extending axial portion 108. Slots110 are provided in the axial portion 18 of torque-transmitting member102 for engagement by teeth 112 on output shaft 13. The sheet metaltorque-transmitting member 102 is formed by drawing an annular sheetmetal member such as to form a shape having portions 108 and 104 andthen partially severing portions 106 at spaced locations around theperiphery of portions 108 from the part in the area of the juncture ofportions 104 and 108 and then bending the portions 106 to theirforwardly extending disposition as shown in FIG. 2. The central radialportion 104 may be joined to the planetary carrier 40 by an known means,which may be, for example, by welding, and in particular an electronbeam welding process. Portion 106 may be joined to annulus gear 44 inany known manner, as for example, by welding, and in particular anelectron beam welding process.

As will be apparent from the above description, there has been provideda transmission that conveniently uses a sheet metal member to transmittorque from either of two elements of the planetary gear set to theoutput shaft and further, the transmission may utilize a transmissioncase 11 which has a servomotor 58 at one end thereof to apply remotely afriction brake mechanism. The transmission case 11, being normally usedfora transmission having an additional gear set and wherein theservomotor 58 is adjacent a friction engaging device, may be used withthe gear set construction shown and described herein due to theutilization of the novel and improved brake mechanism including theannular thrust-transmitting member 78 permitting remote operation ofbrake mechanism 25 by servomotor 58 in its rearward location axiallydisplaced from brake mechanism 25.

Various features of the invention have been particularly shown anddescribed; however, it should be obvious to one skilled in the art thatmodifications may be made therein without departing from the scope ofthe invention.

l claim:

1. A mechanism for transmitting axial thrust including a first memberhaving thrust imparted thereto and a second member axially displacedfrom said first member and said second member receiving axial thrustfrom said first member, comprising means interconnecting said members,said means comprising an axially extending annular sheet metal membersecured to said first member and means securing said annular member tosaid second member whereby axial thrust applied to said first memberwill be transmitted to said second member.

2. A device as claimed in claim 1 wherein said annular member isreceived within a counterbore in said first member said means securingcomprising a projection formed in said annular member to retain saidannular member in said second member.

3. A device as claimed in claim 1 wherein said annular member includesan interruption in the circumference thereof to provide an accessopening through said annular member.

4. In a transmission mechanism including a fluid-actuated servomotor anda friction engaging mechanism, said servomotor and said frictionengaging mechanism being axially displaced, an axially slidable memberin said servomotor movably axially in response to fluid pressure, anaxially movable apply member in said friction engaging mechanism, anannular member connected between said slidable member and said applymember so as to establish a thrust-transmitting relationship betweensame, and said annular member having a tubelike shape and being formedfrom sheet metal.

5. A device as claimed in claim 4 wherein said annular member isreceived within a bore in said axially slidable member.

6. A device as claimed in claim 5 including means formed on said annularmember retaining said apply member thereon.

7. A device as claimed in claim 4 wherein said transmission mechanismincludes a gear set and said servomotor is disposed on one side of saidgear set and said friction device is disposed on the other side of saidgear set, said annular member establishing a thrust-transmittingrelationship between the axially slidable member and said apply member.

8. A transmission mechanism including a planetary gear set having aplurality of intermeshing elements and further including a plurality offriction engaging devices engageable to establish a plurality of gearratios through said transmission, one of said friction engaging devicesbeing disposed adjacent said planetary gear set, a hydraulic mechanismfor applying said'friction engaging mechanism being disposed on theopposite side of said gear set, said hydraulic mechanism including anaxially slidable piston responsive to fluid pressure to be movedaxially, said friction engaging mechanism including an apply membermovable axially to engage the friction engaging mechanism, annular meansinterconnecting said piston and said apply member of said frictionengaging mechanism, said annular means extending axially over the lengthof said planetary gear set, said annular means being of sheet metal andestablishing a thrust-transmitting relationship between said piston andsaid apply member whereby said friction engaging device can be engagedfrom a remote location in said transmission mechanism.

9. A transmission as claimed in claim 8 wherein said annular means isreceived within a bore in said piston and including means securing saidannular means to said piston.

10. A device as claimed in claim 9 further including means securing saidapply member to said annular means.

11. A device as claimed in claim 9 wherein said annular means has aninterrupted portion in the circumference thereof to provide access meansbetween the outer side of said annu lar member and said gear set.

12. A device as claimed in claim 8 wherein said transmission includesfriction engaging devices engageable to connect first or second elementsof said gear set to a power source and said friction engaging mechanismadjacent said gear set comprising means to hold an element of said gearset stationary to establish a particular ratio in said planetary gearset.

13. A device as claimed in claim 12 wherein there is provided a one-waybrake mechanism for said element of said gear set to be held stationaryby said friction brake mechanism adjacent said gear set whereby saidelement is held stationary against rotation in one direction by saidone-way brake and is held stationary in both directions by said frictionengaging mechanism.

14. A transmission mechanism including a planetary gear set having aplurality of intermeshing elements and an output shaft and furtherincluding a plurality of friction engaging devices engageable toestablish a plurality of gear ratios through said transmission, one ofsaid friction engaging devices being disposed adjacent said planetarygear set, a hydraulic mechanism for applying said friction engagingmechanism being disposed on the opposite side of said gear set, saidhydraulic mechanism including an axially slidable piston responsive tofluid pressure to be moved axially, said friction engaging mechanismincluding an apply member movable axially to engage the frictionengaging mechanism, annular means interconnecting said piston and saidapply member of said friction engaging mechanism, said annular meansextending axially over the length of said planetary gear set, saidannular means being of sheet metal and establishing athrust-transmitting relationship between said piston and said applymember whereby said friction engaging device can be engaged from aremote location in said transmission mechanism, and said planetary gearset including a torquetransmitting member connected to at least two ofsaid gear set elements and to said output shaft, saidtorque-transmitting member being formed of sheet metal and having acentral radial portion and forwardly and rearwardly extending axialportions.

15. A transmission mechanism as claimed in claim 14 wherein saidforwardly extending axial portion of said torque transmitting member isconnected to one of said gear set elements and said central radialportion is connected to another element of said gear set.

16. A transmission mechanism as claimed in claim 14 wherein saidforwardly extending portion of said torque-transwherein said rearwardlyextending portion of said torquetransmitting member has means formedtherein for connection to said output shaft.

1. A mechanism for transmitting axial thrust including a first memberhaving thrust imparted thereto and a second member axially displacedfrom said first member and said second member receiving axial thrustfrom said first member, comprising means interconnecting said members,said means comprising an axially extending annular sheet metal membersecured to said first member and means securing said annular member tosaid second member whereby axial thrust applied to said first memberwill be transmitted to said second member.
 2. A device as claimed inclaim 1 wherein said annular member is received within a counterbore insaid fiRst member said means securing comprising a projection formed insaid annular member to retain said annular member in said second member.3. A device as claimed in claim 1 wherein said annular member includesan interruption in the circumference thereof to provide an accessopening through said annular member.
 4. In a transmission mechanismincluding a fluid-actuated servomotor and a friction engaging mechanism,said servomotor and said friction engaging mechanism being axiallydisplaced, an axially slidable member in said servomotor movably axiallyin response to fluid pressure, an axially movable apply member in saidfriction engaging mechanism, an annular member connected between saidslidable member and said apply member so as to establish athrust-transmitting relationship between same, and said annular memberhaving a tubelike shape and being formed from sheet metal.
 5. A deviceas claimed in claim 4 wherein said annular member is received within abore in said axially slidable member.
 6. A device as claimed in claim 5including means formed on said annular member retaining said applymember thereon.
 7. A device as claimed in claim 4 wherein saidtransmission mechanism includes a gear set and said servomotor isdisposed on one side of said gear set and said friction device isdisposed on the other side of said gear set, said annular memberestablishing a thrust-transmitting relationship between the axiallyslidable member and said apply member.
 8. A transmission mechanismincluding a planetary gear set having a plurality of intermeshingelements and further including a plurality of friction engaging devicesengageable to establish a plurality of gear ratios through saidtransmission, one of said friction engaging devices being disposedadjacent said planetary gear set, a hydraulic mechanism for applyingsaid friction engaging mechanism being disposed on the opposite side ofsaid gear set, said hydraulic mechanism including an axially slidablepiston responsive to fluid pressure to be moved axially, said frictionengaging mechanism including an apply member movable axially to engagethe friction engaging mechanism, annular means interconnecting saidpiston and said apply member of said friction engaging mechanism, saidannular means extending axially over the length of said planetary gearset, said annular means being of sheet metal and establishing athrust-transmitting relationship between said piston and said applymember whereby said friction engaging device can be engaged from aremote location in said transmission mechanism.
 9. A transmission asclaimed in claim 8 wherein said annular means is received within a borein said piston and including means securing said annular means to saidpiston.
 10. A device as claimed in claim 9 further including meanssecuring said apply member to said annular means.
 11. A device asclaimed in claim 9 wherein said annular means has an interrupted portionin the circumference thereof to provide access means between the outerside of said annular member and said gear set.
 12. A device as claimedin claim 8 wherein said transmission includes friction engaging devicesengageable to connect first or second elements of said gear set to apower source and said friction engaging mechanism adjacent said gear setcomprising means to hold an element of said gear set stationary toestablish a particular ratio in said planetary gear set.
 13. A device asclaimed in claim 12 wherein there is provided a one-way brake mechanismfor said element of said gear set to be held stationary by said frictionbrake mechanism adjacent said gear set whereby said element is heldstationary against rotation in one direction by said one-way brake andis held stationary in both directions by said friction engagingmechanism.
 14. A transmission mechanism including a planetary gear sethaving a plurality of intermeshing elements and an output shaft andfurther including a plurality of friction engaging devices engageable tOestablish a plurality of gear ratios through said transmission, one ofsaid friction engaging devices being disposed adjacent said planetarygear set, a hydraulic mechanism for applying said friction engagingmechanism being disposed on the opposite side of said gear set, saidhydraulic mechanism including an axially slidable piston responsive tofluid pressure to be moved axially, said friction engaging mechanismincluding an apply member movable axially to engage the frictionengaging mechanism, annular means interconnecting said piston and saidapply member of said friction engaging mechanism, said annular meansextending axially over the length of said planetary gear set, saidannular means being of sheet metal and establishing athrust-transmitting relationship between said piston and said applymember whereby said friction engaging device can be engaged from aremote location in said transmission mechanism, and said planetary gearset including a torque-transmitting member connected to at least two ofsaid gear set elements and to said output shaft, saidtorque-transmitting member being formed of sheet metal and having acentral radial portion and forwardly and rearwardly extending axialportions.
 15. A transmission mechanism as claimed in claim 14 whereinsaid forwardly extending axial portion of said torque transmittingmember is connected to one of said gear set elements and said centralradial portion is connected to another element of said gear set.
 16. Atransmission mechanism as claimed in claim 14 wherein said forwardlyextending portion of said torque-transmitting member is defined bypartially severed sections of said rearwardly extending portion, whichare bent to extend forwardly.
 17. A transmission mechanism as claimed inclaim 14 wherein said rearwardly extending portion of saidtorque-transmitting member has means formed therein for connection tosaid output shaft.